The public switched telephone network (PSTN) has evolved into an efficient real-time, multimedia communication session tool wherein users can pick up any one of nearly one billion telephones and dial any one of nearly one billion endpoints. Several developments have enabled this automated network, such as numbering plans, distributed electronic switching and routing, and networked signaling systems.
Similar to the manner in which the PSTN is based on a hierarchy, the Internet is based on an Internet protocol (IP). Multimedia packets are routed or forwarded from one link to the next (i.e., from a source of a data flow to a destination of the data flow). Each multimedia packet comprises an IP address, which, in Internet protocol version 4 (IPv4), for example, has 32 bits. Each IP address also has a certain number of bits dedicated to a network portion and a certain number of bits dedicated to a host portion.
IP routers are used to transmit a multimedia packet from one network (or link) and place the packet onto another network (or link). Tables are located within IP routers, wherein the tables contain information or criteria used to determine a best way to route the multimedia packet. An example of this information may be the state of network links and programmed distance indications. By using intelligent devices on both sides of a network domain, it is possible to allocate a temporary address to route a multimedia packet through a network and restore the original address on the far side of the network when the packet leaves the network. This is the basis for many current virtual private network (VPN) products and is understood in the art.
To ensure that the network elements (e.g., switches in the telephone network, routers in the data network) can perform their associated tasks, it helps for the network elements to know the status of adjacent communication links and available routes; signaling systems are used to provide this information. In telephone networks, signaling systems used are either signaling system number 7 (SS7) or are equivalent to SS7. An SS7 network is separate from a voice network, and is used for the purpose of switching data messages pertaining to the business of connecting telephone calls and maintaining the signaling network. In addition, the SS7 digital signaling standard is utilized to interface the PSTN to the IP world. As is known by those skilled in the art, SS7 utilizes a message structure wherein messages travel from one network entity to another, independent of the actual voice and data to which they pertain. This message structure utilizes an envelope, referred to as a packet, for traversing messages.
During transmission of a multimedia packet to a destination, network elements may change source and/or destination addresses for the multimedia packet. Unfortunately, the process of determining and changing source and destination addresses within multimedia packets is time consuming, thereby inhibiting high-speed multimedia packet transmission.